Field of the Invention
The present invention is related to torsion bar for tilting cabin of an automobile, particularly related to torsion bar having different number of serration on its both ends, which can improve the assembling work of the torsion bar and the tilting effect of the cabin. When assembling the torsion bar, at least one serration on both ends of the torsion bar get automatically arranged in straight line and torque is not applied on the torsion bar.
Generally driver's room mounted on automobile such as truck and heavy equipment for guarding the driver is called cabin.
A suspension is mounted under the cabin for absorbing the shock from the ground and improving riding feeling. The suspension is positioned between the axle shaft and the body of the vehicle.
A hinge bracket and a torsion bar arm are mounted on both sides of the suspension. A torsion bar is mounted between the hinge bracket and the torsion bar arm. The torsion bar is fixed on the frame of the cabin.
The torsion bar serves as a pivot shaft of the cabin, when the cabin is tilted forward from the horizontal state for inspecting the engine and the shassis under the cabin of the vehicle. Therefore the torsion bar is closely related to the effect of operation for tilting of the cabin.
The effect of tilting operation is caused by the diameter of the torsion bar and the facility for mounting the torsion bar.
The facility for mounting the torsion bar is that little torque can be applied to the torsion bar, when the male serration on the both ends of the torsion bar is engaged with the female serration or a hinge bracket and a torsion bar arm.
FIG. 1 is a perspective view to show the torsion bar assembled to the frame of the cabin according to the prior art. FIG. 2 is a perspective view to show the prior torsion bar disassembled from the hinge bracket and the torsion bar arm.
Generally, a hinge bracket 112 is assembled to an end of the torsion bar 114 and a torsion bar arm 116 is assembled to the other end of the torsion bar 114. And the torsion bar 114 is horizontally set to the under frame of the cabin. The torsion bar 114 is assembled to the hinge bracket 112 and the torsion bar arm 116 respectively with serration 120 shaped on its both ends.
A grip 118 is provided on the lower end of the cabin 100, which is tilted forward from the body of the vehicle using the grip 118 for inspecting the engine and the shassis under the cabin.
The serration is shaped on the both ends of the torsion bar 114. In the prior torsion bar the number of each serration provided on the both ends are equal. Traditionally the number of serration is adopted one of the 40 EA and 38 HA selectively.
Then according to the above, as the same number of the serration 120 is shaped on the both ends of the torsion bar 114, it is very difficult for each teeth comprising the serration shaped on the both ends of torsion bar to be arranged in straight line, when shaping the serration on the both ends of the torsion bar. If each teeth of the serration on the both ends is not matched to each other, torque is occurred on the torsion bar 114, when the torsion bar is assembled to the hinge bracket 112 and the torsion bar arm 116.
The torque applied on the torsion bar make that the gap between the torsion bar and the under frame of the cabin be reduced. The result of that, it is impossible that the torsion bar is fitted to the under frame of the cabin or much effort is required for tilting the cabin forward.